But the terms of the survey state that it will adopt a neutral position, unless there is a 60 per cent majority for or against.

Previous polls found 44 per cent said the college should be formally opposed, with 31 per cent backing a neutral stance, and 25 per cent wanting it to support assisted dying.

A free vote in the Commons in 2015 rejected proposals that would have allowed people with less than six months to live to be prescribed drugs to end their lives with the approval of two doctors and a judge.

John Saunders, a former chairman of the college's ethics committee, has threatened a judicial review of the poll, saying it is "manifestly unreasonable" that if it delivers the same result as a 2014 vote it will change the position.

The new poll of GPs was commissioned by Campaign for Dignity in Dying, which is calling for a change in the law to allow assisted dying.

The survey, carried out by research company medeConnect, also asked family doctors what they would want for themselves.

GPs were asked: “If you were terminally ill and suffering unbearably at the end of life with only months or weeks to live would you personally want or not want the choice of assisted dying in order to control the manner and timing of your death?”

In total, 43 per cent said they would want the option of assisted dying , while 27 per cent said they would not. The remainder did not know or chose not to answer.

Dr Jacky Davis, Chairman of Healthcare Professionals for Assisted Dying, said: “These results show what we know to be true, that there’s no consensus amongst doctors when it comes to the subject of assisted dying. Because of that, most doctors think their medical colleges and representative bodies should adopt a neutral stance so that everyone’s views can be represented.”

The results of the poll by the Royal College of Physicians will be released next month.

Professor Andrew Goddard, RCP president, said: “The Royal College of Physicians is frequently asked for its stance on this high profile issue, which may be cited in legal cases and parliamentary debate, so it is essential that we base this on an up-to-date understanding of our members’ and fellows’ views.”

"Because doctors are divided on the issue, the RCP wants to ensure that we only hold a position one way or another if there is a clear majority view. If the vote is for a neutral position this would mean that the RCP neither supported nor opposed a change in the law, and could reflect the differing views of its members. This should not be taken to mean support for a change in the law to allow assisted dying.”